[Elecraft] KPA500 Hum when off?

[Jack Berry]

My kit built hums but only periodically - more like a cycle and certainly not a continuous hum. When it happens I can fear it if the room is quiet. Capacitor recharging?


On Jun 11, 2013, at 12:13 PM, Stan AE7UT <AE7UTE at gmail.com> wrote:

> I have a kit-built KPA500 that has the same issue.
> It's well grounded and all the bolts are tight.
> The humm is barely noticeable when off but definitely there.
> 
> 73
> Stan AE7UT
> 
> 
> 
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